This is a question about digital/physical art. I thought it might fit in here - if not please excuse the intrusion.

I am looking to commission a painting or digital work from an artist - who happens to be my sister. She is a published artist who is well embedded in the fantasy/fiction environment. She has done book covers, games, cards etc in a variety of mediums.

The only thing is that she will not give me a real answer about cost. I am going to get her to do a 18x20 piece for me and want to pay her fair market value. I have no idea what that would be.  She just says "pay me whatever". I appreciate her being nice - but I want to be nice back at here!

Are there any artists out there that could give me an idea of cost for either digital, acrylic or oil fantasy portrait from a moderately successful artist?

Thanks

The physical costs of the print and framing are easy to look up.

The costs of her effort can be figured as hours-spent times hourly-rate. Find out how much time she will be putting into the project then base your "purchase" on what you think her time is worth.

Very hard to say. You're talking about an original piece of artwork commissioned from a 'moderately successful' artist. I have a brother in law who sells prints of his originals and he's turned down low 4 figures for his originals. As she's a relative I'm sure she expects you to pay some unrealistically low price that she'll take because it's for her brother. For your consideration though, a highly detailed acrylic/oil painting in that size can easily take an artist a week or more (depending on how highly detailed). If you really want to be nice to her offer $1k for the work and she'll probably be thrilled that you recognize the value of her talent. Most likely she'll decline and insist on less. Whatever you do don't offer $100 and think that's generous.

In full disclosure my BIL has a policy of never selling his originals nor does he take commissions. As a result someone would have to bring an unreasonably large check to buy one of his oils.

The above is my opinion and as I'm not an artist it's worth less then you paid for it.

Thanks all. She will not say what her hourly rate is so that one is out.  I was thinking 1k-2k would be decent. Sounds like that may not be bad for a relative price.

Here are some real world prices from a very talented woman.
I have known her for more than 15 years and have seen her work first hand and can vouch for her talent
Terri Miller

 
I know a guy who does water color for people that want a portrait of their car. Something large enough to hang in a rich guy's "garage" runs about 5K from what I've been told. 1-2K would probably be in line for something of the size mentioned if she's that good.